ENGINE UNIT INSPECTION

Using a gasket scraper, remove all the gasket material from the cylinder block contact surface.

Using a wire brush, remove all the carbon from the combustion chambers.

Using a valve guide bushing brush and solvent, clean all the valve guide bushes.

Using a soft brush and solvent, thoroughly clean the cylinder head.

Using a precision straightedge and feeler gauge, measure the warpage of the contact surface between the cylinder head and cylinder block, and the cylinder head and manifolds.

If the warpage is more than the maximum, replace the cylinder head sub-assembly.

Using a dye penetrant, check the intake ports, exhaust ports and cylinder surface for cracks.

If there are cracks, replace the cylinder head sub-assembly.

Using a vernier caliper, measure the outside thread diameter of the bolt.

If the diameter is less than the minimum, replace the cylinder head bolt.

Temporarily install the No. 1 and No. 4 camshaft bearing caps with the 4 bolts by hand.

Uniformly tighten the 24 bolts in several steps in the order shown in the illustration.

Torque:

for 12 mm head bolt of No. 1 and No. 4 camshaft bearing cap

21 N*m  { 214 kgf*cm, 15 ft.*lbf }

for 10 mm head bolt of No. 3 camshaft bearing cap

10 N*m  { 102 kgf*cm, 7 ft.*lbf }

Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.

If the thrust clearance is more than the maximum, replace the camshaft.

If necessary, replace the cylinder head sub-assembly.

Temporarily install the No. 1 and No. 4 camshaft bearing caps with the 4 bolts by hand.

Uniformly tighten the 24 bolts in several steps in the order shown in the illustration.

Torque:

for 12 mm head bolt of No. 1 and No. 4 camshaft bearing cap

21 N*m  { 214 kgf*cm, 15 ft.*lbf }

for 10 mm head bolt of No. 3 camshaft bearing cap

10 N*m  { 102 kgf*cm, 7 ft.*lbf }

Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.

If the thrust clearance is more than the maximum, replace the camshafts.

If necessary, replace the cylinder head sub-assembly.

Inspect the camshaft for runout.

1. Place the camshaft on V-blocks.

2. Using a dial indicator, measure the runout at the center journal.

   Maximum runout
   0.03 mm (0.00118 in.)

   If the runout is more than the maximum, replace the camshaft.

Inspect the cam lobe height.

1. Using a micrometer, measure the cam lobe height.

   Standard Cam Lobe Height
   Item Specified Condition No. 2 and No. 3 camshaft (intake) 37.277 to 37.387 mm (1.468 to 1.472 in.) No. 1 and No. 4 camshaft (exhaust) 38.324 to 38.434 mm (1.509 to 1.513 in.)

   Minimum Cam Lobe Height
   Item Specified Condition No. 2 and No. 3 camshaft (intake) 37.277 mm (1.468 in.) No. 1 and No. 4 camshaft (exhaust) 38.324 mm (1.509 in.)

   If the cam lobe height is less than the minimum, replace the camshaft.

Inspect the camshaft journal diameter.

1. Using a micrometer, measure the journal diameter.

   Standard Journal Diameter
   Item Specified Condition No. 1 journal 29.969 to 29.985 mm (1.180 to 1.181 in.) Other journal 26.969 to 26.985 mm (1.0618 to 1.0624 in.)

   If the journal diameter is not as specified, check the oil clearance.

Lay a strip of Plastigage across each of the camshaft journals.

Temporarily install the camshaft bearing cap with the 4 bolts by hand.

Uniformly tighten the 20 bolts in several steps in the order shown in the illustration.

Torque:

for 12 mm head bolt of No. 1 and No. 4 camshaft bearing cap

21 N*m  { 214 kgf*cm, 15 ft.*lbf }

for 10 mm head bolt of No. 3 camshaft bearing cap

10 N*m  { 102 kgf*cm, 7 ft.*lbf }

Uniformly loosen and remove the 20 bolts in the sequence shown in the illustration.

Measure the Plastigage at its widest point.

If the oil clearance is more than the maximum, replace the camshaft.

If necessary, replace the cylinder head sub-assembly.

Turn the roller by hand to check that it turns smoothly.

If the roller does not turn smoothly, replace the valve rocker arm.

Check the movement of the plunger and bleed air.

Inspect the inner compression spring free length.

1. 

   Using a vernier caliper, measure the free length of the inner compression spring.

   Standard free length
   45.9 mm (1.81 in.)

   If the free length is not as specified, replace the inner compression spring.

Inspect the inner compression spring tension.

1. 

   Using a spring tester, measure the tension of the inner compression spring at the specified installed length.

   Installed tension
   219 to 242 N (22 to 25 kgf, 49.2 to 54.4 lbf) at 31.0 mm (1.22 in.)

   If the installed tension is not as specified, replace the inner compression spring.

Using a caliper gauge, measure the inside diameter of the guide bush.

Using a gasket scraper, chip off any carbon from the valve head.

Inspect the valve stem diameter.

1. Using a micrometer, measure the diameter of the valve stem.

   Standard Valve Stem Diameter
   Item Specified Condition Intake 5.970 to 5.985 mm (0.2350 to 0.2356 in.) Exhaust 5.960 to 5.975 mm (0.2346 to 0.2352 in.)

Inspect the valve face angle.

1. Grind the valve enough to remove pits and carbon.

2. Check that the valve is ground to the correct valve face angle.

   Standard valve face angle
   45.5°

Inspect the valve head margin thickness.

1. Using a vernier caliper, measure the valve head margin thickness.

   Standard margin thickness
   1.0 mm (0.0394 in.)

   Minimum margin thickness
   0.5 mm (0.0197 in.)

   If the margin thickness is less than the minimum, replace the valve.

Inspect the valve overall length.

1. Using a vernier caliper, measure the overall length.

   Standard Overall Length
   Item Specified Condition Intake 104.4 mm (4.11 in.) Exhaust 104.1 mm (4.10 in.)

   Minimum Overall Length
   Item Specified Condition Intake 104.1 mm (4.10 in.) Exhaust 103.8 mm (4.09 in.)

   If the overall length is less than the minimum, replace the valve.

Inspect the valve stem tip.

1. Check the surface of the valve stem tip for wear.

   Note

   Do not grind the valve so it becomes shorter than the minimum overall length.

   If the valve stem tip is worn, resurface the tip with a grinder or replace the valve.

Using a 45° carbide cutter, resurface the valve seats.

Apply a light coat of Prussian blue to the valve face.

Apply a light coat of Prussian blue to the valve face.

Visually check the cylinder for vertical scratches.

If necessary, replace the cylinder block.

Using a precision straightedge and feeler gauge, measure the warpage of the contact surface between the cylinder head and cylinder head gaskets.

If the warpage is more than the maximum, replace the cylinder block sub-assembly.

Using a vernier caliper, measure the tension portion diameter of the bolt.

If the diameter is less than the minimum, replace the connecting rod bolt.

Using a vernier caliper, measure the outside thread diameter of bolt A and B.

If the diameter is less than the minimum, replace the crankshaft bearing cap bolt.

Using a micrometer, measure the piston diameter at a right angle to the piston pin center line, 12 mm (0.472 in.) from the piston skirt.

If the diameter is less than the minimum, replace the piston with pin sub-assembly.

Using a cylinder gauge, measure the cylinder bore diameter at positions A and B in the thrust and axial directions.

If the diameter is more than the maximum, replace the cylinder block.

Check each mark on the piston, piston pin and connecting rod.

Using a caliper gauge, measure the inside diameter of the piston pin hole.

Using a micrometer, measure the piston pin diameter.

Using a caliper gauge, measure the inside diameter of the connecting rod bush.

Using a feeler gauge, measure the clearance between a new piston ring and the wall of the ring groove.

If the clearance is not as specified, replace the piston.

Insert the piston ring into the cylinder bore.

Using a feeler gauge, measure the end gap.

If the end gap is more than the maximum, replace the piston ring. If the end gap is more than the maximum even with a new piston ring, replace the cylinder block.

Using a rod aligner and feeler gauge, check the connecting rod alignment.

1. Check for bend.

   Maximum bend
   0.07 mm (0.00276 in.) per 100 mm (3.94 in.)

   If the bend is more than the maximum, replace the connecting rod sub-assembly.

2. 

   Check for twist.

   Maximum twist
   0.15 mm (0.00591 in.) per 100 mm (3.94 in.)

   If the twist is more than the maximum, replace the connecting rod sub-assembly.

Using a dial indicator and V-blocks, measure the runout as shown in the illustration.

If the circle runout is more than the maximum, replace the crankshaft.

Using a micrometer, measure the diameter of each main journal.

If the diameter is not as specified, check the oil clearance. If necessary, replace the crankshaft.

Using a micrometer, measure the diameter of each crank pin.

If the diameter is not as specified, check the oil clearance. If necessary, replace the crankshaft.

Align the bearing claw with the claw groove of the cylinder block, and push in the 5 upper bearings.

Align the bearing claw with the claw groove of the main bearing cap, and push in the 5 lower bearings.

Place the crankshaft on the cylinder block.

Lay a strip of Plastigage across each journal.

Examine the front marks and numbers and install the crankshaft bearing caps to the cylinder block.

Temporarily install the crankshaft bearing cap bolts labeled A or the bolts labeled B.

Set the 2 cylinder block stiffening plates on the cylinder block.

Step 1:

1. Apply a light coat of engine oil to the threads and under the heads of the 20 crankshaft bearing cap bolts.

2. Install the 20 crankshaft bearing cap bolts. Using several steps, tighten the bolts uniformly in the sequence shown in the illustration.

   Torque:

   for bolt A

   35 N*m  { 357 kgf*cm, 26 ft.*lbf }

   for bolt B

   60 N*m  { 612 kgf*cm, 44 ft.*lbf }

Step 2:

1. Mark the front side of the crankshaft bearing cap bolts A and B with paint.

2. Tighten the crankshaft bearing cap bolts A and B 90° in the sequence shown in the illustration.

Step 3:

1. Tighten the crankshaft bearing cap bolts A another 90° in the sequence shown in the illustration.

2. 

   Check that the painted marks of bolts A are now at a 180° angle to the front.

3. 

   Check that the painted marks of bolts B are now at a 90° angle to the front.

   Note

   Do not turn the crankshaft.

Step 4:

1. Using several steps, install the 10 crankshaft bearing cap bolts uniformly in the sequence shown in the illustration.

   Torque:

   56 N*m  { 571 kgf*cm, 41 ft.*lbf }

Remove the 2 cylinder block stiffening plates.

Using 2 crankshaft bearing cap set bolts, pull out the 5 bearing caps.

Measure the Plastigage at its widest point.

If the oil clearance is more than the maximum, use an over size bearing and correct or regrind the crankshaft so that the oil clearance is as shown in the table below.

If replacing a bearing, replace it with one that has the same number. If the number of the bearing cannot be determined, select the correct bearing by adding together the numbers imprinted on the cylinder block and crankshaft, then refer to the appropriate bearing number. There are 7 sizes of standard bearings, marked "1", "2", "3", "4", "5", "6" and "7" accordingly.

EXAMPLE

Cylinder block main journal bore diameter "1" (A) + Crankshaft main journal diameter "2" (B) = Total number 3 (use bearing "3" (C))

Lay a strip of Plastigage across the crank pin.

Install the connecting rod cap so that its protrusion is facing the correct direction.

Step 1:

1. Install and alternately tighten the bolts of the connecting rod cap in several steps.

   Torque:

   35 N*m  { 357 kgf*cm, 26 ft.*lbf }

Step 2:

1. Mark the front side of each connecting rod cap bolt with paint.

2. Tighten the bearing cap bolts in step 1 90°.

Measure the Plastigage at its widest point.

If the oil clearance is more than the maximum, replace the bearings. If necessary, replace the crankshaft.

If replacing a bearing, replace it with one that has the same number marked on the connecting rod. There are 5 sizes of standard bearings, marked "1 ", "2", "3", "4" and "5" accordingly.

Select the correct bearing by adding together the number marks imprinted on the connecting rod and crankshaft.

EXAMPLE

Connecting rod "1" (A) + Crank pin "2" (B) = Total number 3 (use bearing "3" (C))

Using a spring scale, pull the No. 1 chain with a force of 147 N (15 kgf, 33.1 lbf) and measure the length of the No. 1 chain using a vernier caliper.

If the elongation is more than the maximum, replace the No. 1 chain.

Using a spring scale, pull the No. 2 chain with a force of 147 N (15 kgf, 33.1 lbf) and measure the length of the No. 2 chain using a vernier caliper.

If the elongation is more than the maximum, replace the No. 2 chain.

Wrap the No. 1 chain around the sprocket place for the No. 1 chain.

Wrap the No. 2 chain around the sprocket place for the No. 2 chain.

Wrap the No. 1 chain around the sprocket.

Wrap the No. 2 chain around the sprocket.

Using a micrometer, measure the No. 1 idle gear shaft diameter.

Using a caliper gauge, measure the inside diameter of the idle gear.

Move the stopper plate clockwise to release the lock. Push the plunger and check that it moves smoothly.

If necessary, replace the No. 1 chain tensioner assembly.

Move the stopper plate clockwise to release the lock. Push the plunger and check that it moves smoothly.

If necessary, replace the No. 2 chain tensioner assembly.

Measure the worn depth of the No. 1 chain tensioner slipper.

If the depth is more than the maximum, replace the No. 1 chain tensioner slipper.

Measure the worn depth of the No. 2 chain tensioner slipper.

If the depth is more than the maximum, replace the No. 2 chain tensioner slipper.

Measure the worn depth of the No. 1 chain vibration damper.

If the depth is more than the maximum, replace the No. 1 chain vibration damper.

Measure the worn depth of the No. 2 chain vibration damper.

If the depth is more than the maximum, replace the No. 2 chain vibration damper.

Push the check valve with a pin to check if it is stuck.

If stuck, replace the No. 1 oil nozzle sub-assembly.

While covering A, apply air into B. Check that air does not leak through C. Perform the check again while covering B and applying air into A.

If air leaks, clean or replace the No. 1 oil nozzle sub-assembly.

Push the check valve while covering A, and apply air into B. Check that air passes through C. Perform the check again while covering B, pushing the check valve and applying air into A.

If air does not pass through C, clean or replace the No. 1 oil nozzle sub-assembly.

Using a precision straightedge and feeler gauge, measure the warpage of the contact surface between the No. 1 and No. 3 intake manifold, and the No. 1 intake manifold and cylinder head.

If the warpage is more than the maximum, replace the No. 1 intake manifold.

Using a precision straightedge and feeler gauge, measure the warpage of the contact surface between the No. 2 and No. 3 intake manifold, and the No. 2 intake manifold and cylinder head.

If the warpage is more than the maximum, replace the No. 2 intake manifold.

Using a precision straightedge and feeler gauge, measure the warpage of the contact surface between the No. 3 and No. 1 intake manifold, the No. 3 and No. 2 intake manifold, and the No. 3 intake manifold and intake pipe.

If the warpage is more than the maximum, replace the No. 3 intake manifold.

Using a precision straightedge and feeler gauge, measure the warpage of the contact surface between the exhaust manifold and cylinder head.

If the warpage is more than the maximum, replace the exhaust manifold.